The present invention relates to an image forming apparatus, particularly to an image forming apparatus equipped with toner recycling device.
An image forming apparatus equipped with toner recycling device has been very popular but, because recycled toner deteriorates image quality, preventive measures against it have been taken.
The Patent Document 1 proposes an image forming apparatus in which a toner recycle mode for conveying the toner collected by a cleaning member to a developing device and a toner disposal mode for accumulating the waste toner collected by a cleaning member into a collection container are automatically selectable.
In an image forming apparatus like the above, the toner disposal mode for discharging toner into a collection container is selected when image quality is given the first priority and the toner recycle mode is selected when toner consumption needs to be saved to minimize the running cost.
Patent Document 1 Japanese non-examined Publication Application No. 10-307520
The image forming apparatus of the Patent Document 1 is equipped with an automatic recycling/disposal switching system on a conveyance path for conveying toner from the cleaning member to the developing device and, by switching the automatic recycling/disposal switching system, the toner recycle mode and toner disposal mode are automatically switched.
Switching by an automatic switching system like the above involves a problem that the system may not operate correctly because of its complicated mechanism including couplings and gears.
The selection as to whether the toner recycle mode is used or the toner disposal mode used is not frequently changed but most image forming apparatuses are used in one mode for a long time and then switched to another mode. This is because, once the apparatus is installed in an office, it is very rare that users change their way of usage and accordingly the usage mode of the apparatus seldom changes. It is only in case the machine is moved to another location or reused by different users that the usage mode (or application mode) changes. When the usage mode significantly changes, the toner recycle mode and toner disposal mode are switched.
On an apparatus having been put in service for a long time, small gaps in a toner conveyance path or the like have been clogged with toner and accordingly switching the toner conveyance path is difficult in many cases. In an apparatus like the one in the Patent Document 1 in which the toner recycle mode and toner disposal mode are switched by an automatic switching system comprising complicated mechanism provided on a toner conveyance path, it is likely to happen that the automatic switch system for disposal does not operate correctly.
In addition, since the automatic recycling/disposal switching system of the Patent Document 1 comprises complicated mechanism and contains a number of components, it involves a high cost problem.